In recent years, a thermal-assisted magnetic recording scheme is received a lot of attention as a technology of making high-density magnetic recording enable. The thermal-assisted magnetic recording scheme converts a laser beam generated by a light source (a laser diode) into a near-field light beam using a light irradiation element (a near-field element), and irradiates a part of a recording layer of a magnetic disk with the light beam to locally raise the temperature of the magnetic disk. Then, the heated portion is applied with a magnetic field by a magnetic write head to magnetically record data. It is desirable that the data recorded by the thermal-assisted magnetic recording scheme be improved in reliability.